This invention relates to the operation of numerically controlled machine tools and, more specifically, to an apparatus for locating a starting point for numerical controlled machining operations.
Numerically controlled machine tools, such as milling machines, are coming into greater use in the machining of complex parts requiring machining to very precise tolerances. While machining is very rapid once begun, set-up and adjustment of a workpiece at the start of operations is complex and time consuming. The workpiece must be precisely located at a "zero reference" starting position. Errors in positioning the workpiece can result in a scrapped part.
Presently, a zero reference point on a workpiece is located using machine bed markings, dial micrometers, etc. Two operators are generally required, and accuracy is entirely dependent on the skill of the operators.
Thus, there is a continuing need for a faster, more reliable, method and apparatus for locating a zero reference starting position for numerically controlled machine tools.